Algebraic Expressions

See the terms of a polynomial as colored cards: terms are like terms only when they contain the same letters with the same exponents. Tap two like-term cards to group and combine them, watch the coefficient-adding animation, then write the simplified result.

Compare removing brackets with a plus versus a minus in a step-by-step animation: the minus flips the sign of every term inside. Watch the demo to internalize the rule, then judge whether the expanded result of a random small expression is right or wrong.